1. Field of the Invention
The present invention relates generally to methods, systems and apparatus for identifying and otherwise tracking various conditions and states of features, such as safety devices and equipment, in a transit system, and in particular to a system and method for identifying the condition of upcoming features (such as safety devices, conditions, arrangements, etc.) associated with a track over which a train traverses within a track network.
2. Description of Related Art
Train control systems are used for monitoring and tracking trains traversing tracks throughout a track network. In order to make appropriate train control decisions regarding how the train should be operated, whether manually, automatically or semi-automatically, important information must be obtained. Accurate data and knowledge regarding the conditions of the tracks and surrounding areas in the track network lead to better and more effective control decisions for train operation. Presently, track networks extend throughout all of the countries in the world, and include many interconnected tracks that extend through both populated and unpopulated areas. For example, many train tracks extend through towns, cities, residential areas, etc., such that these tracks intersect other vehicular transit systems, such as roadways. Therefore, and due to the physics and restraints upon operating a train, appropriate safety arrangements are required at such intersections in order to ensure the safety of other vehicles and pedestrians.
As discussed, grade crossings where train and motorists/pedestrian traffic meet require some means of protection and/or safety to warn motorists or pedestrians that a train is moving towards the crossing. Normally, such crossings include flashing lamps and/or crossing gates that prevent access to the road/rail intersection. Failure of the lamps or crossing gates forces the railroad to employ some backup arrangement for protecting the crossing, normally in the form of flagging. Through this flagging arrangement, local law enforcement personnel (or representatives of the railroad) warn motorists and pedestrians of the oncoming train, and the lack of protective and operational safety equipment.
When such a flagging arrangement is in place for both sides of the crossing, the train may operate and proceed through the grade crossing at a normal speed. However, if flagging is only available for one side of the crossing (or on neither side), the train is only permitted to move through the grade crossing at a restricted speed, e.g., 15 mph, and may even have to stop at the crossing depending upon the device failure. Presently, the locomotive or train operator is informed of faulty crossings through a conversation over the voice radio, and the operator must then make some note of the upcoming crossing and act accordingly.
There are available different systems and methods for communicating with wayside equipment, or otherwise implementing some safety features according to the prior art. For example, one or more of the following patents/publications describe train monitoring, control and/or safety systems or functions for use in effectively operating a train in the track network: U.S. Pat. Nos. 7,236,860; 7,036,774; 6,996,461; 6,863,246; 6,845,953; 6,824,110; 6,609,049, all to Kane et al.; U.S. Pat. No. 6,688,561 to Mollet et al.; U.S. Pat. No. 5,452,870 to Heggestad; 2006/0080009 to Kane et al.; 2006/0015224 to Hilleary; 2005/0110628 to Kernwein et al.; and 2004/0182970 to Mollet et al.
These prior art systems and methods exhibit various drawbacks and deficiencies. Further, many of these prior art systems are amenable to further augmentation or beneficial, functional enhancements in order to provide increased vigilance and maintenance of safe conditions at various portions along the track. In addition and when it comes to safety on and along the tracks in a track network, further safety features and functions to protect motorists and pedestrians is of the utmost importance.